I've completed it in around 5 hours. It was some earlier version though, i don't really remember which one.

Spoiler:

Use very light (=> fast reload) lancer VTOLs as early defense; they can also be used to shoot down enemy VTOLs. Scout a bit ahead to the west to spot tanks earlier in the canyon, but avoid enemy AA. Use VTOLs to take a few oil drums around, and build a few tanks (cannon scorpions look good) to capture the oil derrick at the scavenger base on the shore. Build a proxy repair facility (as far as i remember, it's possible to put it near the derrick) and then use bunker buster hover harass to attack the enemy base from the west; you can use heavy mobile ripples to kill enemy ripple emplacements as well.